Antibiotic-induced intestinal microbiota depletion can attenuate the acute kidney injury to chronic kidney disease transition via NADPH oxidase 2 and trimethylamine-N-oxide inhibition

Intestinal microbiota and their metabolites affect systemic inflammation and kidney disease outcomes. Here, we investigated the key metabolites associated with the acute kidney injury (AKI)-to chronic kidney disease (CKD) transition and the effect of antibiotic-induced microbiota depletion (AIMD) on this transition. In 61 patients with AKI, 59 plasma metabolites were assessed to determine the risk of AKI-to-CKD transition. An AKI-to-CKD transition murine model was established four weeks after unilateral ischemia-reperfusion injury (IRI) to determine the effects of AIMD on the gut microbiome, metabolites, and pathological responses related to CKD transition. Human proximal tubular epithelial cells were challenged with CKD transition-related metabolites, and inhibitory effects of NADPH oxidase 2 (NOX2) signals were tested. Based on clinical metabolomics, plasma trimethylamine N-oxide (TMAO) was associated with a significantly increased risk for AKI-to-CKD transition [adjusted odds ratio 4.389 (95% confidence interval 1.106-17.416)]. In vivo, AIMD inhibited a unilateral IRI-induced increase in TMAO, along with a decrease in apoptosis, inflammation, and fibrosis. The expression of NOX2 and oxidative stress decreased after AIMD. In vitro, TMAO induced fibrosis with NOX2 activation and oxidative stress. NOX2 inhibition successfully attenuated apoptosis, inflammation, and fibrosis with suppression of G2/M arrest. NOX2 inhibition (in vivo) showed improvement in pathological changes with a decrease in oxidative stress without changes in TMAO levels. Thus, TMAO is a key metabolite associated with the AKI-to-CKD transition, and NOX2 activation was identified as a key regulator of TMAO-related AKI-to-CKD transition both in vivo and in vitro.

Skin microbe-dependent TSLP-ILC2 priming axis in early life is co-opted in allergic inflammation

Although early life colonization of commensal microbes contributes to long-lasting immune imprinting in host tissues, little is known regarding the pathophysiological consequences of postnatal microbial tuning of cutaneous immunity. Here, we show that postnatal exposure to specific skin commensal Staphylococcus lentus (S. lentus) promotes the extent of atopic dermatitis (AD)-like inflammation in adults through priming of group 2 innate lymphoid cells (ILC2s). Early postnatal skin is dynamically populated by discrete subset of primed ILC2s driven by microbiota-dependent induction of thymic stromal lymphopoietin (TSLP) in keratinocytes. Specifically, the indole-3-aldehyde-producing tryptophan metabolic pathway, shared across Staphylococcus species, is involved in TSLP-mediated ILC2 priming. Furthermore, we demonstrate a critical contribution of the early postnatal S. lentus-TSLP-ILC2 priming axis in facilitating AD-like inflammation that is not replicated by later microbial exposure. Thus, our findings highlight the fundamental role of time-dependent neonatal microbial-skin crosstalk in shaping the threshold of innate type 2 immunity co-opted in adulthood.

Intermittent Fasting Attenuates Metabolic-Dysfunction-Associated Steatohepatitis by Enhancing the Hepatic Autophagy-Lysosome Pathway

An intermittent fasting (IF) regimen has been shown to protect against metabolic dysfunction-associated steatohepatitis (MASH). However, the precise mechanism remains unclear. Here, we explored how IF reduced hepatic lipid accumulation, inflammation, and fibrosis in mice with MASH. The mice were fed a high-fat diet (HFD) for 30 weeks and either continued on the HFD or were subjected to IF for the final 22 weeks. IF reduced body weight, insulin resistance, and hepatic lipid accumulation in HFD-fed mice. Lipidome analysis revealed that IF modified HFD-induced hepatic lipid composition. In particular, HFD-induced impaired autophagic flux was reversed by IF. The decreased hepatic lysosome-associated membrane protein 1 level in HFD-fed mice was upregulated in HFD+IF-fed mice. However, increased hepatic lysosomal acid lipase protein levels in HFD-fed mice were reduced by IF. IF attenuated HFD-induced hepatic inflammation and galectin-3-positive Kupffer cells. In addition to the increases in hepatic hydroxyproline and lumican levels, lipocalin-2-mediated signaling was reversed in HFD-fed mice by IF. Taken together, our findings indicate that the enhancement of the autophagy-lysosomal pathway may be a critical mechanism of MASH reduction by IF.

Multivariable model of postoperative delirium in cardiac surgery patients: proteomic and demographic contributions

Background

Delirium following cardiac surgery is common, morbid, and costly, but may be prevented with risk stratification and targeted intervention. Preoperative protein signatures may identify patients at increased risk for worse postoperative outcomes, including delirium. In this study, we aimed to identify plasma protein biomarkers and develop a predictive model for postoperative delirium in older patients undergoing cardiac surgery, while also uncovering possible pathophysiological mechanisms.

Methods

SOMAscan analysis of 1,305 proteins in the plasma from 57 older adults undergoing cardiac surgery requiring cardiopulmonary bypass was conducted to define delirium-specific protein signatures at baseline (PREOP) and postoperative day 2 (POD2). Selected proteins were validated in 115 patients using the ELLA multiplex immunoassay platform. Proteins were combined with clinical and demographic variables to build multivariable models that estimate the risk of postoperative delirium and bring light to the underlying pathophysiology.

Results

A total of 115 and 85 proteins from SOMAscan analyses were found altered in delirious patients at PREOP and POD2, respectively (p<0.05). Using four criteria including associations with surgery, delirium, and biological plausibility, 12 biomarker candidates (Tukey's fold change (|tFC|)>1.4, Benjamini-Hochberg (BH)-p<0.01) were selected for ELLA multiplex validation. Eight proteins were significantly altered at PREOP, and seven proteins at POD2 (p<0.05), in patients who developed postoperative delirium compared to non-delirious patients. Statistical analyses of model fit resulted in the selection of a combination of age, sex, and three proteins (angiopoietin-2 (ANGPT2); C-C motif chemokine 5 (CCL5); and metalloproteinase inhibitor 1 (TIMP1); AUC=0.829) as the best performing predictive model for delirium at PREOP. The delirium-associated proteins identified as biomarker candidates are involved with inflammation, glial dysfunction, vascularization, and hemostasis, highlighting the multifactorial pathophysiology of delirium.

Conclusion

Our study proposes a model of postoperative delirium that includes a combination of older age, female sex, and altered levels of three proteins. Our results support the identification of patients at higher risk of developing postoperative delirium after cardiac surgery and provide insights on the underlying pathophysiology. ClinicalTrials.gov ( NCT02546765 ).

Development of reference material for quality control of uranium analysis in marine sediments

Environmental radioactivity monitoring is strengthening due to public concerns over radioactive contamination since the Fukushima nuclear power plant accident. Therefore, various research laboratories, institutes, and universities have been conducting environmental radioactivity surveys around nuclear power plants (NPPs). However, the reliability of the results continues to trigger controversy in society. This study was conducted to develop reference material (RM) for the quality control of 238U and 234U analyses in marine sediments. The RM was prepared according to ISO Guides 31, 34, and 35. A homogeneity test of the marine sediment RM was implemented by analyzing two batch samples from ten bottles using multiple acid digestion and alkali fusion, respectively. We found that the 238U and 234U reference values of the RM were 43.0 ± 1.7 Bq kg-1(k=1) and 41.5 ± 1.9 Bq kg-1(k=1), respectively. This marine sediment RM will be useful for the quality control of analytical methods for similar samples and proficiency tests.

Development of metal radioactive liquid reference material for proficiency test

This study developed liquid reference materials containing various metals, to be used for quality assurance of radiation measurements of the most common metallic wastes generated during the operation or decommissioning of nuclear power plants. The liquid reference materials were prepared by assuming the dissolution of stainless-steel using acid and melting of the major metals present in the stainless steel, namely Fe, Ni, Cr, and Mn, along with the standard sources (134Cs, 137Cs, 60Co, 90Sr). The theoretical massic activity of the standard sources added to the samples and the measured reference values of the gamma and beta emitters in the samples were compared, and they showed good agreement within a one-sigma confidence interval (k = 1). Using the developed reference materials, a proficiency test was conducted on three domestic labs, and the results were evaluated using Z-score. While the evaluation results showed good agreement between the reference values and the reported values for 137Cs and 60Co, all participating labs reported lower values than the reference value for 134Cs. For 90Sr, two out of the three labs reported significantly higher values than the reference value. Based on the results of this study, the developed metal radioactive liquid reference material is expected to be registered as certified reference material (CRM) in the future. They will be used as the CRM for measuring and ensuring the quality of radioactive metal waste.

The lipoprotein-associated phospholipase A2 inhibitor Darapladib sensitises cancer cells to ferroptosis by remodelling lipid metabolism

Arachidonic and adrenic acids in the membrane play key roles in ferroptosis. Here, we reveal that lipoprotein-associated phospholipase A2 (Lp-PLA2) controls intracellular phospholipid metabolism and contributes to ferroptosis resistance. A metabolic drug screen reveals that darapladib, an inhibitor of Lp-PLA2, synergistically induces ferroptosis in the presence of GPX4 inhibitors. We show that darapladib is able to enhance ferroptosis under lipoprotein-deficient or serum-free conditions. Furthermore, we find that Lp-PLA2 is located in the membrane and cytoplasm and suppresses ferroptosis, suggesting a critical role for intracellular Lp-PLA2. Lipidomic analyses show that darapladib treatment or deletion of PLA2G7, which encodes Lp-PLA2, generally enriches phosphatidylethanolamine species and reduces lysophosphatidylethanolamine species. Moreover, combination treatment of darapladib with the GPX4 inhibitor PACMA31 efficiently inhibits tumour growth in a xenograft model. Our study suggests that inhibition of Lp-PLA2 is a potential therapeutic strategy to enhance ferroptosis in cancer treatment.

Urine myo-inositol as a novel prognostic biomarker for diabetic kidney disease: a targeted metabolomics study using nuclear magnetic resonance

BACKGROUND

As a leading cause of chronic kidney disease, clinical demand for noninvasive biomarkers of diabetic kidney disease (DKD) beyond proteinuria is increasing. Metabolomics is a popular method to identify mechanisms and biomarkers. We investigated urinary targeted metabolomics in DKD patients.

METHODS

We conducted a targeted metabolomics study of 26 urinary metabolites in consecutive patients with DKD stage 1 to 5 (n = 208) and healthy controls (n = 26). The relationships between estimated glomerular filtration rate (eGFR) or urine protein-creatinine ratio (UPCR) and metabolites were evaluated. Multivariate Cox analysis was used to estimate relationships between urinary metabolites and the target outcome, end-stage renal disease (ESRD). C statistics and time-dependent receiver operating characteristics (ROC) were used to assess diagnostic validity.

RESULTS

During a median 4.5 years of follow-up, 103 patients (44.0%) progressed to ESRD and 65 (27.8%) died. The median fold changes of nine metabolites belonged to monosaccharide and tricarboxylic acid (TCA) cycle metabolites tended to increase with DKD stage. Myo-inositol, choline, and citrates were correlated with eGFR and choline, while mannose and myo-inositol were correlated with UPCR. Elevated urinary monosaccharide and TCA cycle metabolites showed associations with increased morality and ESRD progression. The predictive power of ESRD progression was high, in the order of choline, myo-inositol, and citrate. Although urinary metabolites alone were less predictive than serum creatinine or UPCR, myo-inositol had additive effect with serum creatinine and UPCR. In time-dependent ROC, myo-inositol was more predictive than UPCR of 1-year ESRD progression prediction.

CONCLUSION

Myo-inositol can be used as an additive biomarker of ESRD progression in DKD.

xCT-mediated glutamate excretion in white adipocytes stimulates interferon-γ production by natural killer cells in obesity

Obesity-mediated hypoxic stress underlies inflammation, including interferon (IFN)-γ production by natural killer (NK) cells in white adipose tissue. However, the effects of obesity on NK cell IFN-γ production remain obscure. Here, we show that hypoxia promotes xCT-mediated glutamate excretion and C-X-C motif chemokine ligand 12 (CXCL12) expression in white adipocytes, resulting in CXCR4+ NK cell recruitment. Interestingly, this spatial proximity between adipocytes and NK cells induces IFN-γ production in NK cells by stimulating metabotropic glutamate receptor 5 (mGluR5). IFN-γ then triggers inflammatory activation of macrophages and augments xCT and CXCL12 expression in adipocytes, forming a bidirectional pathway. Genetic or pharmacological inhibition of xCT, mGluR5, or IFN-γ receptor in adipocytes or NK cells alleviates obesity-related metabolic disorders in mice. Consistently, patients with obesity showed elevated levels of glutamate/mGluR5 and CXCL12/CXCR4 axes, suggesting that a bidirectional pathway between adipocytes and NK cells could be a viable therapeutic target in obesity-related metabolic disorders.

Longitudinal study investigating serum metabolites and their association with type 2 diabetes risk in a Korean population

AIM

The lack of longitudinal metabolomics data and the statistical techniques to analyze them has limited the understanding of the metabolite levels related to type 2 diabetes (T2D) onset. Thus, we carried out logistic regression analysis and simultaneously proposed new approaches based on residuals of multiple logistic regression and geometric angle-based clustering for the analysis in T2D onset-specific metabolic changes.

METHODS

We used the 6th, 7th, and 8th follow-up data from 2013, 2015, and 2017 among the Korea Association REsource (KARE) cohort data. Semi-targeted metabolite analysis was performed using ultra performance liquid chromatography/triple quadrupole-mass spectrometry (UPLC/TQ-MS) systems.

RESULTS

Since the results from the multiple logistic regression and a single metabolite in a logistic regression analysis varied dramatically, we recommend using models that consider potential multicollinearity among metabolites. The residual-based approach particularly identified neurotransmitters or related precursors as T2D onset-specific metabolites. By using geometric angle-based pattern clustering studies, ketone bodies and carnitines are observed as disease onset specific metabolites and separated from others.

CONCLUSIONS

To treat patients with early-stage insulin resistance and dyslipidemia when metabolic disorders are still reversible, our findings may contribute to a greater understanding of how metabolomics could be used in disease intervention strategies in the early stages of T2D. This article is protected by copyright. All rights reserved.

Development of concrete reference material for quality assurance/quality control of gamma radioactivity measurement for nuclear power plant decommissioning waste

The Korea Research Institute of Standards and Science has developed a new concrete reference material (RM) for measuring gamma-emitting radionuclides, such as 134Cs, 137Cs, 65Zn, 241Am, and 60Co, to improve and maintain the quality assurance and quality control of the radioactivity measurement in radioactive waste generated during the decommissioning of nuclear power plants. In this study, cement, SiO2, and bentonite, which are the main components of concrete, were mixed in an appropriate ratio with radionuclides. For certification and homogeneity assessment, 10 bottles were randomly selected, two sub-samples were collected from each bottle, and radionuclides were measured via HPGe gamma spectrometry. The results of the homogeneity tests using a one-way analysis of variance on 241Am, 134Cs, 137Cs, 65Zn, and 60Co in the concrete RM fulfilled the requirements of ISO Guide 35. Coincidence summing and self-absorption correction were performed on measurement results by introducing the Monte Carlo efficiency transfer code and Monte Carlo N-Particle transport code. The reference values for five radionuclides (60Co, 65Zn, 241Am, 134Cs, and 137Cs) in the RM were in the range of 15-40 Bq/kg, and the expanded uncertainty was within 10% (k = 2). To the best of our knowledge, this was the first study to develop concrete RM for measuring gamma-emitting radionuclides.

Associations between local acidosis induced by renal LDHA and renal fibrosis and mitochondrial abnormalities in patients with diabetic kidney disease

During the progression of diabetic kidney disease (DKD), renal lactate metabolism is rewired. The relationship between alterations in renal lactate metabolism and renal fibrosis in patients with diabetes has only been partially established due to a lack of biopsy tissues from patients with DKD and the intricate mechanism of lactate homeostasis. The role of lactate dehydrogenase A (LDHA)-mediated lactate generation in renal fibrosis and dysfunction in human and animal models of DKD was explored in this study. Measures of lactate metabolism (urinary lactate levels and LDHA expression) and measures of DKD progression (estimated glomerular filtration rate and Wilms' tumor-1 expression) were strongly negatively correlated in patients with DKD. Experiments with streptozotocin-induced DKD rat models and the rat renal mesangial cell model confirmed our findings. We found that the pathogenesis of DKD is linked to hypoxia-mediated lactic acidosis, which leads to fibrosis and mitochondrial abnormalities. The pathogenic characteristics of DKD were significantly reduced when aerobic glycolysis or LDHA expression was inhibited. Further studies will aim to investigate whether local acidosis caused by renal LDHA might be exploited as a therapeutic target in patients with DKD.

NMR-based metabolomic analysis of human plasma to examine the effect of exposure to persistent organic pollutants

Persistent organic pollutants (POPs) are lipophilic environmental toxins, and the level of chemicals accumulated in the body through the food chain has been linked to the incidence of diseases such as type 2 diabetes, cardiovascular disease, and cancer. We analyzed the concentration of POPs and circulating metabolites and investigated the associations between the concentration of plasma metabolites and the levels of polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) to determine the effect of the accumulation of POPs in human samples. Metabolic profiling of plasma from 276 Korean participants was performed using ¹H nuclear magnetic resonance (NMR) and statistical analyses. The concentrations of PCBs and OCPs in each sample were measured. Correlation analysis and a covariate-adjusted general linear model (GLM) were used to investigate the association of the concentration of POPs with circulating metabolites in human blood samples. We found that four categories of Σ6PCBs and Σ5OCPs based on rank were significantly correlated with 4 and 5 metabolites, respectively, after adjusting for confounding factors, including age, sex, body mass index (BMI), smoking status, alcohol intake, physical activity, triglycerides, and total cholesterol. According to the GLM analyses, 3 metabolites, namely, creatinine, acetate, and formate, among the 4 correlated metabolites were associated with four categories of rank-based Σ6PCBs. On the other hand, the quartiles of the rank-based Σ5OCPs were not associated with any circulating metabolites among the 5 correlated metabolites. Our findings indicate that the metabolites related to short-chain fatty acids and creatine can be useful risk indicators for estimating the effect of PCB exposure.

Integrated metagenomics and metabolomics analysis illustrates the systemic impact of the gut microbiota on host metabolism after bariatric surgery

AIM

To explore how bariatric surgery (BS) modified the obesity-associated gut microbiome, the host metabolome, and their interactions in obese Korean patients.

MATERIALS AND METHODS

Stool and fasting blood samples were obtained before and 1, 3, 6, and 12 months after BS from 52 patients enrolled in the Korean Obesity Surgical Treatment Study. We analysed the gut microbiome by 16S rRNA gene sequencing and the serum metabolome, including bile acids, by nuclear magnetic resonance spectroscopy and ultrahigh-performance liquid chromatography/triple quadrupole mass spectrometry.

RESULTS

Stool metagenomics showed that 27 microbiota were enriched and 14 microbiota were reduced after BS, whereas the abundances and diversity of observed features were increased. The levels of branched-chain amino acids and metabolites of energy metabolism in serum were decreased after surgery, whereas the levels of metabolites related to microbial metabolism, including dimethyl sulphone, glycine, and secondary bile acids, were increased in the serum samples. In addition, we found notable mutual associations among metabolites and gut microbiome changes attributed to BS.

CONCLUSIONS

Changes in the gut microbiome community and systemic levels of amino acids and sugars were directly derived from anatomical changes in the gastrointestinal tract after BS. We hypothesized that the observed increases in microbiome-related serum metabolites were a result of complex and indirect changes derived from BS. Ethnic-specific environmental or genetic factors could affect Korean-specific postmetabolic modification in obese patients who undergo BS.

Lipidomic profiling analysis of human plasma from subjects with hypercholesterolemia to evaluate the intake of yellow yeast rice fermented by Aspergillus terreus DSMK01

Yellow yeast rice (YYR) is a Korean functional food fermented with Aspergillus terreus and contains monacolin K, a cholesterol-lowering ingredient. However, the effects of YYR on lipid metabolism alterations have not been reported until now. In this study, we performed a mass spectrometry-based lipidomic analysis of plasma samples from subjects (31 from the YYR group and 27 from the placebo group) with LDL-C higher than 130 mg dL^-1 to investigate the effects of the intake of YYR. Lipidomic profiling showed that the levels of sphingomyelin (SM) were significantly decreased in the YYR intake group compared with the placebo group. The SM level in the YYR intake group showed a significant association with the ApoB/ApoA1 ratio (p = 0.004, r = 0.503), an indicator of the effect of lipid-lowering therapy. This study suggests that global lipidomic profiling could be used to identify changes in lipid metabolism induced by YYR intake and provide information that these lipid changes are associated with improved hypercholesterolemia.

POS1060 CHANGES IN DISEASE ACTIVITY AND PATIENT-REPORTED OUTCOMES IN PSORIATIC ARTHRITIS PATIENTS TREATED WITH IXEKIZUMAB IN A REAL-WORLD US COHORT

Background

Ixekizumab (IXE), an IL-17A inhibitor, has demonstrated efficacy in clinical trials1-3 but real-world effectiveness (RWE) data are limited.4

Objectives

To describe changes in disease activity and patient-reported outcomes (PROs) at 6 and 12 months follow-up among psoriatic arthritis (PsA) patients initiating IXE in a routine clinical setting.

Methods

This retrospective cohort study included patients from the OM1 PsA Registry (OM1, Boston, MA), a linked electronic medical record and administrative claims dataset with over 50,000 patients. Eligible patients had ≥1 prescription for IXE (first = index), were ≥18 years old at index, had ≥1 diagnosis code for PsA in the 12 months before or on index, and had ≥12 months of baseline and ≥6 months of follow-up data as of June 2021. For patients with baseline and follow-up measures available, changes in Clinical Disease Activity Index (CDAI), PROs, and other clinical outcomes from baseline to 6 and 12 months were described. For patients on IXE monotherapy, change in CDAI score from baseline to 6 and 12 months was assessed using mixed effects linear models adjusted for age, sex, and baseline CDAI score.

Results

The study population included 1,812 patients with a mean age of 53.7 years (Table 1). Psoriasis was present in 82% and enthesitis in 28%. Over 60% of patients were obese, and the mean Charlson Comorbidity Index was 1.3. Most patients (84%) had prior treatment with a biologic disease-modifying antirheumatic drug (bDMARD) and 40% with a targeted synthetic DMARD (tsDMARD). The mean number of bDMARDs and tsDMARDs used during all available prior history was 2.3 and 1.1, respectively. The most common prior bDMARDs were secukinumab (n=428, 24%) and adalimumab (n=245, 14%).

Table 1.

Demographic and Clinical Characteristics by Therapy Status

All Patients(N=1,812)Monotherapy(N=1,485)Combination Therapy(N=327)Age (years)Mean (s.d.)53.7 (12.2)53.9 (12.3)52.9 (11.7)Median (Q1-Q3)55 (46-62)55 (46-62)54 (45-61)SexFemale1,108 (61.1%)909 (61.2%)199 (60.9%)Male704 (38.9%)576 (38.8%)128 (39.1%)Charlson Comorbidity IndexMean (s.d.)1.3 (1.6)1.3 (1.6)1.5 (1.7)Median (Q1-Q3)1 (0-2)1 (0-2)1 (0-2)BMIUnderweight: <18.510 (0.6%)10 (0.7%)0 (0.0%)Normal weight: 18.5-24.9210 (12.2%)172 (12.2%)38 (12.1%)Overweight: 25-29.9455 (26.5%)379 (27.0%)76 (24.2%)Obese: >= 301,045 (60.8%)845 (60.1%)200 (63.7%)Missing927913Domains of PsA: PsoriasisYes1,490 (82.2%)1,222 (82.3%)268 (82.0%)No322 (17.8%)263 (17.7%)59 (18.0%)Domains of PsA: EnthesitisYes510 (28.1%)409 (27.5%)101 (30.9%)No1,302 (71.9%)1,076 (72.5%)226 (69.1%)

Of patients with a baseline CDAI score, 61% had moderate or severe disease activity. For all patients, CDAI scores improved (decreased) by an average of 3.4 and 3.7 points at 6 and 12 months, respectively, from a baseline mean of 15.4. All disease activity measures and PROs improved from baseline to 6 and 12 months (Figure 1). In patients persistent with IXE, 35.3% and 33.7% were in CDAI remission or low disease activity at 6 and 12 months after initiation, respectively. For IXE monotherapy users (82% of patients), at baseline, patients had a mean CDAI of 14.3 (n=131) and 15.1 (n=105) for the 6 and 12 month analyses, respectively. Adjusted mean changes in CDAI from baseline to 6 months (-3.6 points, p < 0.0001) and 12 months (-4.9 points, p < 0.0001) were statistically significant.

Conclusion

In this cohort of PsA patients with multiple prior b/tsDMARD failures, improvements in disease activity and PROs were observed at 6 and 12 months after initiating treatment with IXE. Improvements were observed in patients overall and in the monotherapy subgroup. More real-world research on IXE and other bDMARDs are important to understand the effect of treatment choices on clinical and PROs in both bDMARD-naive and experienced PsA patients.

References

[1]Mease PJ. Ann. Rheum. Dis. 2017;76(1):79-87

[2]Nash P. Lancet. 2017;389(10086):2317-2327

[3]Mease PJ. Ann. Rheum. Dis. 2020;79(1):123-131

[4]Berman J. Biologics. 2021 Nov 18;15:463-470

Disclosure of Interests

Julie Birt Shareholder of: Shareholder of Eli Lilly and Company, Employee of: Employee of Eli Lilly and Company, William Tillett Speakers bureau: Abbvie, Amgen, Celgene, Eli-Lilly, Janssen, MSD, Novartis,, Pfizer, UCB, Consultant of: Abbvie, Amgen, Celgene, Eli-Lilly, Janssen, MSD, Novartis, Pfizer, UCB, Grant/research support from: Abbvie, Amgen, Celgene, Eli-Lilly, Janssen, UCB, Cristi Cavanaugh: None declared, Yoojin Jung: None declared, Aisha Vadhariya Shareholder of: Shareholder of Eli Lilly and Company, Employee of: Employee of Eli Lilly and Company, Sarah Ross Shareholder of: Shareholder of Eli Lilly and Company, Employee of: Employee of Eli Lilly and Company, Jess Paulus: None declared, Aubrey Trevelin Sprabery Shareholder of: Shareholder of Eli Lilly and Company, Employee of: Employee of Eli Lilly and Company, Ennio Lubrano: None declared

Integrative Pathway Analysis of SNP and Metabolite Data Using a Hierarchical Structural Component Model

Integrative multi-omics analysis has become a useful tool to understand molecular mechanisms and drug discovery for treatment. Especially, the couplings of genetics to metabolomics have been performed to identify the associations between SNP and metabolite. However, while the importance of integrative pathway analysis is increasing, there are few approaches to utilize pathway information to analyze phenotypes using SNP and metabolite. We propose an integrative pathway analysis of SNP and metabolite data using a hierarchical structural component model considering the structural relationships of SNPs, metabolites, pathways, and phenotypes. The proposed method utilizes genome-wide association studies on metabolites and constructs the genetic risk scores for metabolites referred to as genetic metabolomic scores. It is based on the hierarchical model using the genetic metabolomic scores and pathways. Furthermore, this method adopts a ridge penalty to consider the correlations between genetic metabolomic scores and between pathways. We apply our method to the SNP and metabolite data from the Korean population to identify pathways associated with type 2 diabetes (T2D). Through this application, we identified well-known pathways associated with T2D, demonstrating that this method adds biological insights into disease-related pathways using genetic predispositions of metabolites.

Association between circulating bile acid alterations and nonalcoholic steatohepatitis independent of obesity and diabetes mellitus

BACKGROUND AND AIMS

Bile acid (BA) dysregulation is related to not only metabolic diseases but also nonalcoholic fatty liver disease (NAFLD). We investigated whether circulating BA levels are altered according to the histological severity of NAFLD independent of metabolic derangements.

METHODS

Global metabolic profiling and targeted BA analysis using sera collected from biopsy-proven no-NAFLD (n = 67), nonalcoholic fatty liver (NAFL) (n = 99), and nonalcoholic steatohepatitis (NASH, n = 75) subjects were performed sequentially. Circulating metabolome analysis integrated with the hepatic transcriptome was performed to elucidate the mechanistic basis of altered circulating BA profiles after stratification by obesity (body mass index ≤ 25 kg/m² ). Circulating BA alterations were also validated in an independent validation cohort (29 no-NAFLD, 70 NAFL and 37 NASH).

RESULTS

Global profiling analysis showed that BA was the metabolite significantly altered in NASH compared to NAFL. Targeted BA analysis demonstrated that glyco-/tauro-conjugated primary BAs were commonly increased in nonobese and obese NASH, while unconjugated primary BAs increased only in nonobese NASH. These characteristic primary BA level changes were maintained even after stratification according to diabetes status and were replicated in the independent validation cohort. Compared to nonobese NAFL patients, nonobese NASH patients exhibited upregulated hepatic expression of CYP8B1.

CONCLUSIONS

BA metabolism is dysregulated as the histological severity of NAFLD worsens, independent of obesity and diabetes status; dysregulation is more prominent in nonobese NAFLD patients. Metabolome-driven omics approach provides new insight into our understanding of altered BA metabolism associated with individual phenotypes of NAFLD.

High spatial-density, cladding-pumped 6-mode 7-core fiber amplifier for C-band operation

We present a C-band 6-mode 7-core fiber amplifier in an all-fiberized cladding-pumped configuration for space division multiplexed transmission supporting a record 42 spatial channels. With optimized fiber components (e.g. passively cooled pump laser diode, pump coupler, pump stripper), high power multimode pump light is coupled to the active fiber without any noticeable thermal degradation and an average gain of 18 dB and noise figure of 5.4 dB are obtained with an average differential modal gain of 3.4 dB.

Risk factors for the delayed diagnosis of extrapulmonary TB

BACKGROUND: Extrapulmonary TB (EPTB) is more difficult to diagnose than pulmonary TB. The delayed management of EPTB can lead to complications and increase the socio-economic burden.METHODS: Patients newly diagnosed with EPTB were retrospectively enrolled from 11 general hospitals in South Korea from January 2017 to December 2018. The basic characteristics of patients were described. Univariable and multivariable analyses were performed between early and delayed diagnosis groups to identify risk factors for delayed diagnosis and treatment in EPTB.RESULTS: In total, 594 patients were enrolled. Lymph node TB (28.3%) was the predominant form, followed by abdominal (18.4%) and disseminated TB (14.5%). Concurrent lung involvement was 17.8%. The positivity of diagnostic tests showed no significant difference between the two groups. Acute clinical manifestations in disseminated, pericardial and meningeal TB, and immunosuppression were associated with early diagnosis. Delayed diagnosis was associated with outpatient clinic visits, delayed sample acquisition and diagnostic departments other than infection or pulmonology.CONCLUSION: The delay in diagnosis and treatment of EPTB was not related to differences in microbiological characteristics of Mycobacterium tuberculosis itself; rather, it was due to the indolent clinical manifestations that cause referral to non-TB-specialised departments in the outpatient clinic and delay the suspicion of TB and diagnostic testing.

MULTIPHYSICS MODELING OF PRECURSORS IN MOLTEN SALT FAST REACTORS USING PROTEUS AND Nek5000

The goal of this work was to calculate the impact of the delayed neutron precursor drift in fast spectrum Molten Salt Reactors (MSRs) using coupled solutions from the neutronics code PROTEUS and the computational fluid dynamics code Nek5000. Specifically, using a multiphysics approach to solve the effective delayed neutron fraction (βeff) or delayed neutron precursor distribution for reactors with flowing fuel salts would provide valuable information for transient simulations and safety assessments. Given the multiple options for the flux solution and geometric resolution/fidelity in PROTEUS, two approaches were developed and applied to various test cases: PROTEUS-NODAL/Nek5000 and PROTEUS-SN/Nek5000. For the former, the precursors are tracked in the built-in precursor drift model in PROTEUS-NODAL, whereas in the latter, Nek5000 directly tracks the precursors. Both approaches were used to solve a single test channel problem and showed excellent agreement in the calculated βeff. Separately, a 3D hourglass-shaped core was modeled using the PROTEUS-SN/Nek5000 approach. This problem was designed to demonstrate the capability of the discrete ordinates (SN) solver and Nek5000 to model complex core designs with axially varying geometries and the ability for Nek5000 to track the precursors and calculate the resulting βeff. In addition, the Nek5000 calculations revealed the presence of recirculation zones in the hourglass design, which could lead to significant temperatures in the fuel salt and surrounding materials. These first coupled solutions show why these approaches may be necessary for not only predicting the precursor drift effect in fast MSRs but also for reactor design and performance assessments.

Advances in Mechanical Thrombectomy for Acute Ischemic Stroke Due to Large Vessel Occlusion

Acute ischemic stroke (AIS) is a significant cause of global morbidity and mortality, with functional implications for quality of life and long-term disability. The limitations of intravenous thrombolytic therapy for the treatment of AIS, especially for emergent large vessel occlusion (ELVO), have paved the way for alternative therapies and the rapidly evolving landscape of endovascular therapy (EVT). Here, we summarize the major landmark trials that have advanced the field largely due to ongoing biomedical engineering device development that have translated into significantly improved clinical outcomes. Our review describes the clinical success of EVT, and current and future trends.

Oxytocin receptor expression in stallion testes and epididymides

Endocrine, paracrine, and autocrine factors orchestrate the development and physiology of the stallion reproductive system. Oxytocin (OXT) is one of the critical endocrine, paracrine, and autocrine factors for the male reproductive system. Previous studies have investigated OXT receptor (OXTR) expression in testes and epididymides, including humans, marmosets, macaques, swine, and sheep. This study aimed to explore (1) OXTR localization in the testes and epididymides and (2) the seasonal modification of OXTR expression in the testes. Adult stallion testis and epididymis samples were prepared using routine castration procedures. Reverse-transcription PCR was performed to detect the presence of OXTR messenger RNA (mRNA) in the testes. Western blot procedure was performed to confirm the cross-reactivity of OXTR antibody to horse OXTR. Immunohistochemistry was performed to detect OXTR protein expression in the testes and epididymides. Oxytocin receptor mRNA was detected in the stallion testes. The OXTR protein band was observed at 55 kDa. Interestingly, the relative intensity of the OXTR protein band varied between nonbreeding and breeding season. The OXTR protein level in the testes collected during the breeding season was higher than that during the nonbreeding season. Oxytocin receptor localization was observed in the cytoplasm of Type A spermatogonia and spermatid. Oxytocin receptor protein expression was also observed in the cytoplasmic area of Leydig cells and the membrane of the seminiferous tubules. The cytoplasm of principal and basal cells in the caput, corpus, and cauda was also immunolabeled with OXTR antibody. In conclusion, based on the expression of OXTR in tissues of testes and epididymides, OXT-OXTR system may be a critical factor for stallion testicular and epididymal function. In addition, according to the seasonal alteration of intensity, the OXT-OXTR system may be associated with seasonal changes in the reproductive system in stallions.

Urinary Metabolomic Profiling in Streptozotocin-Induced Diabetic Mice after Treatment with Losartan

Diabetic kidney disease (DKD) is the leading cause of chronic kidney disease and end-stage kidney disease. Renin-angiotensin system inhibitors such as losartan are the predominant therapeutic options in clinical practice to treat DKD. Therefore, it is necessary to identify DKD-related metabolic profiles that are affected by losartan. To investigate the change in metabolism associated with the development of DKD, we performed global and targeted metabolic profiling using 800 MHz nuclear magnetic resonance spectroscopy of urine samples from streptozotocin-induced diabetic mice (DM) with or without losartan administration. A principal component analysis plot showed that the metabolic pattern in the losartan-treated diabetic mice returned from that in the DM group toward that in the control mice (CM). We found that 33 urinary metabolites were significantly changed in DM compared with CM, and the levels of 16 metabolites among them, namely, glucose, mannose, myo-inositol, pyruvate, fumarate, 2-hydroxyglutarate, isobutyrate, glycine, threonine, dimethylglycine, methyldantoin, isoleucine, leucine, acetylcarnitine, 3-hydroxy-3-methylglutarate, and taurine, shifted closer to the control level in response to losartan treatment. Pathway analysis revealed that these metabolites were associated with branched-chain amino acid degradation; taurine and hypotaurine metabolism; glycine, serine, and threonine metabolism; the tricarboxylic acid cycle; and galactose metabolism. Our results demonstrate that metabolomic analysis is a useful tool for identifying the metabolic pathways related to the development of DKD affected by losartan administration and may contribute to the discovery of new therapeutic agents for DKD.

Circulating lipidomic alterations in obese and non-obese subjects with non-alcoholic fatty liver disease

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) affects obese and non-obese individuals. However, mechanisms underlying non-obese non-alcoholic steatohepatitis (NASH) remain unclear.

AIMS

To attempt to identify metabolic perturbations associated with non-obese and obese NAFLD using a lipidomics approach.

METHODS

A cross-sectional analysis of 361 subjects with biopsy-proven NAFLD (157 NAFL and 138 NASH) and healthy controls (n = 66) was performed. Individuals were categorised as obese or non-obese based on the Asian cut-off for body mass index. Circulating lipidomic profiling of sera was performed based on the histological severity of NAFLD. Circulating lipidomic alterations were validated with an independent validation set (154 NAFLD subjects [93 NAFL and 61 NASH] and 21 healthy controls).

RESULTS

Saturated sphingomyelin (SM) species were significantly associated with visceral adiposity in non-obese NAFLD (SM d38:0; P < 0.001) but not in obese NAFLD. Additionally, SM levels were significantly associated with systemic and adipose tissue insulin resistance (SM d38:0; P = 0.002 and <0.001, respectively). Five potential lipid metabolites for non-obese subjects and seven potential lipids for obese subjects were selected to predict NAFLD and NASH. These lipid combinations showed good diagnostic performance for non-obese (area under the curve [AUC] for NAFLD/NASH = 0.916/0.813) and obese (AUC for NAFLD/NASH = 0.967/0.812) subjects. Moreover, distinctly altered patterns of diacylglycerol (DAG), triacylglycerol (TAG) and SM levels were confirmed in the validation set depending on the histological severity of NAFLD.

CONCLUSION

Non-obese and obese NAFLD subjects exhibit unique circulating lipidomic signatures, including DAGs, TAGs and SMs. These lipid combinations may be useful biomarkers for non-obese and obese NAFLD patients.

Fumarate modulates phospholipase A2 receptor autoimmunity-induced podocyte injury in membranous nephropathy

Downstream mechanisms that lead to podocyte injury following phospholipase A2 receptor (PLA2R) autoimmunity remain elusive. To help define this we compared urinary metabolomic profiles of patients with PLA2R-associated membranous nephropathy (MN) at the time of kidney biopsy with those of patients with minimal change disease (MCD) and to healthy individuals. Among the metabolites differentially expressed in patients with PLA2R-associated MN compared to healthy individuals, fumarate was the only significant differentially expressed metabolite in PLA2R-associated MN compared to MCD [fold-difference vs. healthy controls and vs. MCD: 1.76 and 1.60, respectively]. High urinary fumarate levels could predict the composite outcome of PLA2R-associated MN. Fumarate hydratase, which hydrolyzes fumarate, colocalized with podocalyxin, and its expression was lower in glomerular sections from patients with PLA2R-associated MN than in those from healthy individuals, patients with non-PLA2R-associated MN or MCD. Podocytes stimulated with IgG purified from serum with a high anti-PLA2R titer (MN-IgG) decreased expression of fumarate hydratase and increased fumarate levels. These changes were coupled to alterations in the expression of molecules involved in the phenotypic profile of podocytes (WT1, ZO-1, Snail, and fibronectin), an increase in albumin flux across the podocyte layer and the production of reactive oxygen species in podocytes. However, overexpression of fumarate hydratase ameliorated these alterations. Furthermore, knockdown of fumarate hydratase exhibited synergistic effects with MN-IgG treatment. Thus, fumarate may promote changes in the phenotypic profiles of podocytes after the development of PLA2R autoimmunity. These findings suggest that fumarate could serve as a potential target for the treatment of PLA2R-associated MN.

Urinary Metabolomic Profiling Analysis and Evaluation of the Effect of Ecklonia cava Extract Intake

Metabolomics is a powerful tool for the investigation of interactions between diet, nutrients, and human metabolism. Ecklonia cava is an edible brown alga that is abundantly found in Korea and Japan and contains unique polyphenols referred to as phlorotannins. However, there are few metabolomics studies related to the effects of polyphenols in humans. In this study, we performed a mass spectrometry-based metabolomics analysis of urine samples from participants with a body mass index (BMI) higher than 25 kg/m2 and lower than 30 kg/m2 to investigate the effects of the intake of seapolynol isolated from E. cava. Metabolomic profiling showed that the levels of riboflavin, urocanic acid, 5-hydroxy-6-methoxyindole glucuronide, and guanidino valeric acid were significantly increased in the seapolynol intake group compared with the placebo group. A correlation analysis was performed to identify the association between the metabolites' levels and clinical characteristics related to body fat. Among the metabolites whose concentrations changed in the seapolynol intake group, riboflavin was associated with BMI, body weight, fat mass, and percent body fat. These findings suggest that the decreased body fat induced by the intake of seapolynol is related to an increase in the antioxidant effect of riboflavin.

Effects of hydroxycinnamic acids on the reduction of furan and α-dicarbonyl compounds

The effects of hydroxycinnamic acids such as cinnamic acid (CNA), p-coumaric acid(CMA), caffeic acid (CFA), and chlorogenic acid (CGA) on the reduction of furan in canned-coffee model systems (CCMS) containing α-dicarbonyls [glyoxal (GO) or methylglyoxal (MGO)] were investigated. The concentration of furan in CCMS containing GO, which was 59.76 μg/L, was reduced by the addition of CFA and CGA to 48.31 μg/L and 41.38 μg/L, respectively; similarly, the furan concentration in model system containing MGO was 45.79 μg/L, and this decreased to 35.41 μg/L (by CFA) and 32.65 μg/L (by CGA), respectively. In addition, the effects of hydroxycinnamic acids on the trapping of GO and MGO were determined. CFA and CGA greatly reduced the concentration of GO to 303.51 μg/L and 267.80 μg/L, respectively (compared to 515.79 μg/L in the control), whereas that of MGO was decreased to 207.01 μg/L and 219.14 μg/L (compared to 417.14 μg/L in the control). The trapping of α-dicarbonyls such as GO and MGO by CFA and CGA could be closely related to furan reduction in CCMS.

Rapid Characterization and Discovery of Chemical Markers for Discrimination of Xanthii Fructus by Gas Chromatography Coupled to Mass Spectrometry

Xanthii Fructus (XF) is known as a medicinal plant. It has been used as a traditional medicine because of its high biological efficacy. However, there have been few comprehensive studies on the specific chemical composition of the plant and consequently, the information is lacking for the mechanism of the natural product metabolites in humans. In this study, an efficient analytical method to characterize and discriminate two species of Xanthii Fructus (Xanthium canadense Mill. and Xanthium sibiricum Patrin ex Widder) was established. Volatile organic compounds (VOCs), polar metabolites, and fatty acids were classified by integrated sample preparation, which allowed a broad range for the detection of metabolites simultaneously. Gas chromatography-mass spectrometry (GC-MS) followed by a multivariate statistical analysis was employed to characterize the chemical compositions and subsequently to discriminate between the two species. The results demonstrate that the two species possess obviously diverse chemical characteristics of three different classifications, and discriminant analysis was successfully applied to a number of chemical markers that could be used for the discrimination of the two species. Additional quantitative results for the selected chemical markers consistently showed significant differences between the two species.

Cerebral Ketones Detected by 3T MR Spectroscopy in Patients with High-Grade Glioma on an Atkins-Based Diet

BACKGROUND AND PURPOSE

Ketogenic diets are being explored as a possible treatment for several neurological diseases, but the physiologic impact on the brain is unknown. The objective of this study was to evaluate the feasibility of 3T MR spectroscopy to monitor brain ketone levels in patients with high-grade gliomas who were on a ketogenic diet (a modified Atkins diet) for 8 weeks.

MATERIALS AND METHODS

Paired pre- and post-ketogenic diet MR spectroscopy data from both the lesion and contralateral hemisphere were analyzed using LCModel software in 10 patients.

RESULTS

At baseline, the ketone bodies acetone and β-hydroxybutyrate were nearly undetectable, but by week 8, they increased in the lesion for both acetone (0.06 ± 0.03 ≥ 0.27 ± 0.06 IU, P = .005) and β-hydroxybutyrate (0.07 ± 0.07 ≥ 0.79 ± 0.32 IU, P = .046). In the contralateral brain, acetone was also significantly increased (0.041 ± 0.01 ≥ 0.16 ± 0.04 IU, P = .004), but not β-hydroxybutyrate. Acetone was detected in 9/10 patients at week 8, and β-hydroxybutyrate, in 5/10. Acetone concentrations in the contralateral brain correlated strongly with higher urine ketones (r = 0.87, P = .001) and lower fasting glucose (r = -0.67, P = .03). Acetoacetate was largely undetectable. Small-but-statistically significant decreases in NAA were also observed in the contralateral hemisphere at 8 weeks.

CONCLUSIONS

This study suggests that 3T MR spectroscopy is feasible for detecting small cerebral metabolic changes associated with a ketogenic diet, provided that appropriate methodology is used.

CXCR3 ligands in pleural fluid as markers for the diagnosis of tuberculous pleural effusion

SETTING

A tertiary care academic medical centre.

OBJECTIVE

To evaluate the clinical usefulness of C-X-C motif chemokine receptor 3 (CXCR3) ligands in tuberculous pleural effusion (TPE).

DESIGN

We recruited 336 patients with pleural effusion due to various causes. Concentrations of interferon-gamma (IFN-γ) and the CXCR3 ligands CXCL9 and CXCL11 were determined using enzyme immunoassays; adenosine deaminase (ADA) activity was measured in pleural fluid and serum.

RESULTS

TPE was diagnosed in 106 patients. Non-TB conditions included lung cancer (n = 95), para-pneumonic effusion (n = 52), non-lung malignancy (n = 30), other exudate (n = 24) and transudate (n = 29) disorders. All marker levels in serum samples and pleural fluid were significantly higher in the TPE group. Analyses of receiver operating characteristic curves for differentiating TPE from non-TB effusions produced the following results for the area under the curve (AUC) for CXCL9, CXCL11, IFN-γ and ADA, respectively: 0.982, 0.952, 0.982, and 0.952. Marker AUCs in lymphocytic exudates were also high. Combining the levels of CXCL9, IFN-γ and ADA in pleural fluid improved the diagnostic performance. Serum levels of CXCL9 had the highest AUC (0.848) for diagnosing TPE.

CONCLUSION

Levels of CXR3 ligands in pleural effusion are useful for diagnosing TPE.

Lysophosphatidylserine receptor P2Y10: A G protein-coupled receptor that mediates eosinophil degranulation

BACKGROUND

P2Y10, along with GPR34 and GPR174, is a G protein-coupled receptor that is activated by an endogenous lipid mediator lysophosphatidylserine (LysoPS). Its expression pattern and its function are completely unknown. We have previously shown that P2Y10 is one of the highly up-regulated genes at the late differentiation stage during in vitro eosinophilopoiesis.

OBJECTIVE

We explored the expression and functions of P2Y10 in human cord blood (CB)-derived and peripheral blood (PB) eosinophils.

METHODS

Real-time PCR, FACS, Western blot, ELISA, and chemotaxis assays were performed to determine the expression and function of P2Y10.

RESULTS

As CB cells differentiated towards eosinophils, P2Y10 mRNA and protein were abundantly expressed. P2Y10 was the most highly expressed in the granulocytes from PB, to a lesser extent in monocytes, and least in lymphocytes. Further fractionation of granulocytes revealed that eosinophils express P2Y10 much more strongly than do neutrophils. PB eosinophils solely expressed P2Y10 among the three LysoPS receptors, while PB neutrophils expressed the three at comparable levels. LysoPS activated both CB and PB eosinophils to induce a robust ERK phosphorylation. Importantly, LysoPS was capable of triggering degranulation of ECP in PB eosinophils. This response was significantly reduced by pharmacological inhibitors of TNF-alpha-converting enzyme (TACE), epidermal growth factor receptor (EGFR), and ERK1/2, which were known to be required in P2Y10-mediated signalling pathways. However, LysoPS had no effect on chemotaxis, differentiation, or eosinophil survival.

CONCLUSIONS AND CLINICAL RELEVANCE

LysoPS provokes eosinophil degranulation through P2Y10. Therefore, P2Y10 is a potential therapeutic target to control eosinophil-associated diseases.